Fifty years from now if an understanding of man's origins, his evolution, his history, his progress is not in the common place of the school books we shall not exist.

The child is not a prisoner of its inheritance; it holds its inheritance as a new creation which its future actions will unfold.

The hand is the cutting edge of the mind.

Progress is the exploration of our own error. Evolution is a consolidation of what have always begun as errors. And errors are of two kinds: errors that turn out to be true and errors that turn out to be false (which are most of them). But they both have the same character of being an imaginative speculation. I say all this because I want very much to talk about the human side of discovery and progress, and it seems to me terribly important to say this in an age in which most non-scientists are feeling a kind of loss of nerve.

I grew up to be indifferent to the distinction between literature and science, which in my teens were simply two languages for experience that I learned together.

The basis for poetry and scientific discovery is the ability to comprehend the unlike in the like and the like in the unlike.

Many theories of the ancient world seem terribly childish today, a hodge-podge of fables and false comparisons.But our theories will seem childish five-hundred years from now.Every theory is based on some analogy, and sooner or later the theory fails because the analogy turns out to be false. A theory in its day helps to solve the problems of the day.